#include <stdio.h>
#include <ctype.h>
#include <string.h>

#define L 100

void mov(char str[], int len, int delta)
{
    for (int i = 0; i < len; ++i)
    {
        int k = str[i];
        if (!isalpha(k))
        {
            continue;
        }
        k += delta;
        while (k > 'z')
        {
            k -= 'z' - 'a' + 1;
        }
        while (k < 'a')
        {
            k += 'z' - 'a' + 1;
        }
        str[i] = k;
    }
}

int main()
{
    char buf[L];
    int delta = 0;
    scanf("%d%s", &delta, buf);
    mov(buf, strlen(buf), delta);
    printf(buf);
    return 0;
}